A staffer at left-wing Media Matters for America committed numerous felonies in the District of Columbia and around the country by carrying a firearm to defend the organization’s founder, David Brock, The Daily Caller has learned.

According to a knowledgeable source, multiple firearms used to protect the Media Matters founder were purchased with Brock’s blessing — and apparently with the group’s money.

But the extent of Brock’s armed activities have been largely unknown until now, even among those closest to him. An array of current and former Media Matters sources, all with intimate knowledge about the inner workings of the organization, granted extensive interviews to TheDC.

Brock, whose struggles with mental health have seen him hospitalized in the past, became increasingly concerned by late 2010 that he was being targeted by right-wing assassins.

TheDC has learned that by that time, Brock had armed his assistant — who had no permit to carry a concealed firearm — with a Glock handgun.

Between Price-Morris’ early 2009 arrival and late 2010 departure from Media Matters, he also acquired a shotgun for Brock’s protection.

Price-Morris was regularly armed when accompanying Brock on trips around the country, according to a source, and his firearm possession in Washington, D.C. constituted multiple felonies.

On at least one occasion, Brock — accompanied by his armed aide — visited California to attend a “Democracy Alliance” summit of major Democratic donors and lawmakers.

That gathering included such major figures in Democratic politics as billionaires George Soros, Peter Lewis and Bill Benter, former Service Employees International Union Secretary-Treasurer Anna Burger, and the politician behind the federal government’s 1994 “Assault Weapons Ban,” California Democratic Sen. Dianne Feinstein.

On Thursday, Feinstein re-introduced a new version of the ban which would reinstate and greatly expand the law, which expired in 2004. Reached Thursday, a spokesman for Feinstein did not respond to a request for comment related to the senator’s attendance, alongside Brock and Price-Morris, at the Democracy Alliance meeting.

Spokespersons for Soros and Benter did not reply to emailed requests for comment.